How to make a (cardboard) real magnifying glass!

Make your own real magnifying glass (the cardboard version)

Whether they’re exploring the world around them or role-playing as adventurers or spies, kids love playing with a real magnifying glass.

This cardboard, handmade, magnifying glass is just perfect for them to use, and they can decorate it themselves too.

Read on to find out how to make them.

A real magnifying glass made from cardboard
A home-made magnifying glass that’s quick and easy to make.

When I found a pile of lenses in my local Scrapstore, I knew I had the ideal project to use the in. I’d been dying to make my kids their own magnifying glasses for ages, and these lens were perfect for the task

A home-made magnifying glass

I wanted to make a simple ‘holder’ for these lenses to turn them into functional (and fantastic!) real magnifying glasses. If you’ve read my other tutorial, you’ll know that I tried out two designs for my lens holders.

The first (this one) uses a bit of corrugated cardboard, while the other is covered with fabric for a more polished look
Using cardboard to make a magnifying glass is quick and easy.
A home-made, fabric-covered, magnifying glass
This fabric-covered diy magnifying glass is a big hit with adults and kids alike!

If you want to make lots of these, then the cardboard one is probably best as it’s quick and easy to make. As a bonus, the kids can decorate the cardboard any way they like, to make them completely their own.

On the other hand, my kids LOVED the fabric diy magnifying glass. That one makes a lovely gift. However it takes a little longer to make, and you’ll need a few more supplies too.

Home-made diy real magnifying glasses
The amount of magnification will depend on the lens used.
diy cardboard magnifying glasses
These cardboard magnifying glasses would make great party favours.

If you fancy trying out the fabric version, head over to my tutorial here. If you want to give the cardboard version a go, carry on reading!

Using a cardboard real magnifying glass to look at a flower book.
Ditch the plastic and make your own cardboard magnifying glass!

(Product links in this article are Amazon links to materials I used in this diy magnifying glass project. These are all affiliate links – you can find out more on my ‘about affiliate links’ page.)

A note on lenses

You can’t make a real magnifying glass without a lens, and while I was lucky enough to find some at my local Scrapstore, that’s probably not much use to most of you.

Lenses (Scrapstore bargains aside) aren’t cheap, so unless you’re happy to pay upwards of £5, I suggest you either cannibalise an existing magnifying glass for the lens, or use the lens from an old pair of glasses.

My lenses vary in size and shape, but are all at least 50mm in diameter, which is about the smallest I’d want for a kid’s magnifying glass.

Bear in mind that you need a CONVEX lens – a concave lens will make things look smaller, not bigger! This little diagram explains the difference.

Convex lenses for a diy real magnifying glass
Think creatively when sourcing lenses for your magnifying glass.

You can buy convex lenses online – ideally you need a bi-convex / double convex lens (which most ones I found online tended to be). You’ll also need your lenses to have a thin edge.

Instructions for a DIY real magnifying glass

These instructions are for making a cardboard diy magnifying glass.

While these look similar to my fabric-covered diy real magnifying glass, the method and materials does differ significantly, so check out my other tutorial if you’d like to see how to make the fabric-covered magnifying glasses.

A cardboard, home-made magnifying glass
Whether they use it for play or for study, kids love these home-made magnifying glasses

Materials needed

To make your own cardboard, real magnifying glass, you will need:

  • a double / bi-convex lens (make sure it has a thin edge)
  • corrugated cardboard
  • thin brown/kraft card or thin card of your choice of colour!
  • glue or double-sided sticky tape
  • (optional) jewellery cord, coloured string or wool/yarn/ribbon
Materials needed for a diy real magnifying glass
You only need a few simple materials to make a holder for your magnifying lens.

And you will need the following tools:


1. Draw your holder

Using your lens as a guide to size, draw the shape of your lens holder onto the corrugated cardboard.

Make sure that there is a margin of at least 5mm / ¼ inch between the edge of your lens and the edge of the holder.

Making a real magnifying glass
This simple shape is easy for kids to hold, and gives them a nice amount of space to decorate if they want!

You don’t have to make your DIY real magnifying glass the same shape as mine, of course! A hexagon, circle or square, for example, would be really good too and may work better depending on the shape of your lens.

2. The lens aperture

Place your lens on top of your holder where you want it to sit, and draw around it. Then draw a smaller circle inside.

This inner circle (where your lens will sit) should be around 5mm smaller than the actual diameter of your lens. This overlap will hold the lens in place.

DIY real magnifying glass in progress
Cut out your holder, and you are almost done!

2. Cut your cardboard

Cut out your holder and the INNER circle only. Unlike the fabric version, you only need to cut out one piece of cardboard.

Making a real magnifying glass from cardboard
The inner circle is where the lens will sit, while the outer circle holds it in place.

3. Cut your lens aperture

Using a sharp knife, cut slits around the edge of your inner circle, only as far as the outer circle that marks the size of your lens.

Make sure to cut through the TOP layer of your corrugated cardboard only.

These slits are to allow you to pull back the edges so that you can slot your lens between the two outer layers of the corrugated cardboard. However for the lens to fit, you’ll also need to squash down the middle, concertina layer of card all around the circle.

You can use something like the handle of a teaspoon to do this squishing!

DIY real magnifying glass
Hollow out the inner cardboard layer within the larger circle, to make room for your lens.

Once you’ve squashed down that middle layer in the corrugated cardboard where your lens is going to sit, set your corrugated-card holder aside.

We have one more thing to do before inserting the lens.

1. Draw your aperture rims

On your THIN card, draw around your lens and use the holder as a stencil to draw on the inner circle too.

Repeat and then cut out both circles, and remove the inner circles from them both. These will go onto your holder once the lens is in, so set these to one side for now.

Cardboard for a diy real magnifying glass
Cut out two of these frames to go onto your holder once the lens is in.

4. Insert your lens

Going back to your corrugated-cardboard holder, carefully pull back a couple of the outer circle sections you slit earlier.

Insert your lens and gently twist it into place, lifting up other sections as necessary, until the lens is sitting in place.

A diy real magnifying glass in progress
Bend back these outer tabs carefully, only far enough to slot the lens in.

5. Reinforce your aperture

The outer layers of the corrugated cardboard will hold the lens in place securely without the need for any glue. But it will be less secure on the side with the slits (obviously!).

To help reinforce that side, use glue or double-sided tape to stick on one of your thin cardboard rings (the aperture rims we made earlier).

This should cover the slit area completely and make sure the lens can’t fall out.

Adding a frame around the lens in a diy real magnifying glass.
I used plain brown card for these lens frames, but you could use a contrasting colour or patterned card instead.

Stick the other rim onto the reverse of your holder. Adding a ring to this side is just decorative so you could leave it off. As it doesn’t have slits, this side should be strong enough to hold the lens in place without reinforcement.

6. Add your cord

If you want to have your DIY real magnifying glass on a cord for carrying or wearing, then simply punch a hole or two in the corner(s), and thread some string, wool, or ribbon through.

a pair of diy real magnifying glasses
All finished!

It may sound silly, but do be careful if you are giving this to a young child.

Cords can be a strangulation hazard for children so I am always very cautious with anything going around the neck. Use your own common sense about what is right for your child. Be sure to supervise little ones when they are wearing these.

A home-made real magnifying glass made from cardboard
All finished – all you have to decide now is whether to leave it plain or decorate…

7. Decorate!

And that’s it! Your DIY real magnifying glass is all finished and ready to decorate, or to use in all its brown cardboard glory!

A home-made magnifying glass made out of cardboard
Make your own real magnifying glass out of cardboard and an old lens!

There’s no end to the variety you can add to these through choice of shape and material alone. If you make a DIY magnifying glass of your own, I’d love to see it!

Want to try the fabric version? Head over to that tutorial instead…

Two home-made real magnifying glasses - one fabric, one cardboard.
These DIY magnifying glasses are easy to make, whether you go for the fabric-covered one or the even-simpler cardboard version!

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Using cardboard to make a magnifying glass is quick and easy.

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